I would like to find a way to use the 2m repeaters and ping APRS location data while on my 45 mile commute. I thought of the tiny trak but I'm aware of the problems with having both radios on the same band at the same time with their own antennas. Can anyone suggest a duel band mobile rig that can do both? It will be my first experience with APRS. I am not familiar with what models are available.

If you just want to ping your location data while mobile, you might want to look a the AIO (all in one) from Byonics dot com. It is a self contained 10 watt transmitter and gps receiver. Check out their web site. If you are looking to do more with APRS, like sending messages or tracking some one else, then I would look at the Kenwood 710 or the Yaseu FT 350. If you go with the Knwood or Yaseu you will need a GPS unit that can output the position info to the radio. Take a look at APRS.org web site as it will give you a lot of info as to what you can do with APRS. It's more than just vehicle tracking... but that is one aspect of it.

John, I am not sure of how much interference you will get on your other radio set to a different freq. What you should do is place the 2 antennas (assuming you are using the mag mount they sell for the AIO) as far apart as possible. With 10 watts it shouldn't be too bad, but I'll deferr to others as to what amount of interference you may get. You may get some very short periods of de-sense when the AOI xmits.

Expect either receiver to be desensed when the other transmitter is on. This will,of course, be more annoying on the receiver you are listening to than for the APRSreceiver. Spacing between antennas will help, but I usually expect desense at a distance of a couple car lengths, so you probably can't get enough spacing to eliminate the problem entirely unless you drive a semi.

I run APRS and 2 meters all the time. I've had no problem with them interfering with each other. The APRS is one of Byonic's stand alone models (RTG) with a 5/8 wave antenna. The 2 meter antenna is about 5 - 6 feet from the APRS antenna. None of hte local repeaters are near 144.390 Mhz which makes it more practical. - Paul

I often run a 2M/440 dual band radio, a 222 radio, and an APRS tracker with 5 watts out. All on a Chevy Sonic, so not that much space between the antennas.

I have never noticed any effects fro the APRS on 220 and 440.

Occasionally I can hear a little hash on 2M receive as the APRS transmits. Not enough to be objectionable. In more urban areas I drop the APRS to 1 watt and adjust the path, and with the stronger repeater signals I haven't heard anything.

To really judge if a particular setup is going to work for you you may have to try it and see if the issues are enough to bother you.

I would recommend the RTG FA or the RTG 30 ( Soon to be re-released with a 60 Watt amplifier) You will get more power out of the RTG, since it has a virtually infinite supply of DC power and current, and its significantly less expensive. Electronically, the RTG and the AIO are pretty much the same "under the hood". If you are brand new to APRS, there is some learning curve in assembling an encoder ( like the TT3) , cable, and GPS, since the set up requires careful installation to prevent recycling due to RF-induced "swamping" of the TT3 PIC. The RTG is nearly immune to this phenomenon.

As far as noise, some people will notice GPS clock noise ( from any GPS) being present on their HF rigs, or noise bleeding into the AM/FM radio during transmissions. There is always some danger to both devices when antennae are placed into close proximity, especially in the near field, largely presenting as one of the devices blowing out its final amplifier. Usually, the APRS transmitter loses that duel ( notice proper spelling!) since the Voice rig will have a long transmission duty cycle, and the APRS transmitter will typically operate for 300 ms about every two minutes ( depending on how you order/ program the tracker) A mobile radio can induce over 100 Volts into nearby antenna. This is a very rare problem, and with a magnet mount antenna, easily remedied.

The Avmap is awesome! Its supported by Kenwood, and although its more expensive than most GPS display receivers, its the only GPS intended to support APRS. The Byonics TT4 also supports the Avmap, and Avmap has produced custom software features specifically for the TT4. I have a G5 and a G6, and I love them both!

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